op milwaukee



Jan. 5 1932. R. w. MARQUARDT- ,8

BED BOTTOM Filed July 24 1930 Patented Jan. 5, 1932 UNITED STATES PATENT OFFICE REINHOLD W. MARQUARDT, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO MARQUARDT COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN BED BOTTOM Application filed July 24,

This invention relates to improvements in bed bottoms.

It is the object of the invention to provide a novel and improved mechanical connection between the upright helicals of a bed bottom to permit of an unusual degree of flexibility while avoiding permanent distortion.

The invention is particularly applicable to bed bottoms in which the upright helicals or supporting springs have knotted or closed end coils, all. such coils being disposed substantially in a common plane except when the spring is subjected to load. In accordance with this invention, each such top coil is provided on opposite sides with a portion offset from such plane and providing a substantially horizontal strand adapted to be associated in lateral proximity with the corresponding strand of adjacent supporting helicals. By means of the vertical offset it is my purpose to greatly facilitate the application of horizontal or spacing helicals which are twisted or screwed about the contiguous strands of the helicals of successive rows whereby operatively to bind the top coils of the upright helicals together in hinged relation.

In the drawings:

Figure 1 is a plan view of a fragment of a bed bottom embodying this invention.

Figure-2 is a perspective view on an en larged scale showing one of the upright or supporting helical springs in its proper relation to a fragment of another spring and the horizontal spring which holds the uprights together.

Figure 3 is a further enlarged detail in plan of the union between two adjacent upright springs.

Figure 4 is a fragmentary detail, taken in section in the plane indicated at 4-4 of Figure 3.

F'gure 5 shows a modified construction embodying the invention as illustrated in a plane view similar to Figure 3.

Like parts are identified by the same reference characters throughout the several views.

Each of the upright helical springs 6 is preferably of hour glass form having en- 1930. Serial No. 470,322.

larged top and bottom coils 7 and 8, each of which is closed by a knot as at 9.

At corresponding positions of the sides of the top and bottom coils, each such coil is provided with offsets toward the center of the helical spring. Each such ofi'set involves integral upright strands 10 and 11 and a connecting strand 12 which is substantially horizontal and parallel to the general planes of the top and bottom coils 7 and 8.

The upright supporting springs 6 are disposed in rows as shown in Figure 1, in which view the rows are disposed transversely of the sheet. The small diameter connecting springs 15 are used in preference to other connecting means to connect the top coils of supporting springs adjacent in each row and to connect the springs of adjacent rows to each other.

This is accomplished by feeding the connecting springs 15 across the offset portions of the end coils of contiguous springs while rotating the helical connectors 15. By so doing, the helical connector is caused to encircle the strands 12 and abut the upright strands 10 and 11 at each end thereof, as clearly shown in Figures 2, 3 and 4. axis of the connecting springs 15will, in each instance, be slightly toward the center of the bed bottom from the' horizontal plane in which the end coils of the several upright springs are disposed. Due to the pitch of the connecting springs 15 it will be observed in Figures 2 and 3 that the upright strands 10 and 11 are slightly offset from the corresponding uprightstrands of the contiguous spring length thereto. By virtue of this arrangement a high degree of flexibility is assured and each spring may move independ-- ently of the contiguous spring to which it is linked and its end coil may assume angular positions varying in each direction from the horizontal with respect to the contiguous spring as shown in Figure at.

Another way of securing flexibility between contiguous coils of adjacent supporting springs independently of the pitch of the connecting spring 15, consists in providing different lengths of horizontal strands 12 and 12' to be held by the connecting heli- The cal 15 in the relation in which they are illustrated in Figure 5.

The offset of the connecting strands 12 from the plane of the end coils of the springs is a very important feature of the invention as it greatly facilitates the application of the connecting helicals 15 and greatly facilitates hinged movement between closed coils. It is more diflicult to provide a suitable hinged connection between closed coils than to make such a connection between open coiled springs in which the ends of the coils are free for alignment. By using open coiled springs, however, the rigidity and permanence of the closed coil construction is sacrificed. The constructions disclosed are particularly strong and durable while having an unusual degree of flexibility. Furthermore, the offset of the connecting springs 15 beneath the general plane of the top and bottom coils of the fabric tends to eliminate completely any tendency of bed clothing or mattress material to become entangled in the joint between component springs of the structure. It will be understood that the construction here illustrated is suitable for use in a bed spring,

a spring mattress or in spring upholstery generally, although for convenience, it has here been designated as a bed bottom.

I claim:

1. In a spring structure, the combination with a pair of adjacent supporting springs having complementar contiguous portions axially offset inward y to provide upright strands and horizontal strands, of a connecting spring including a helical coil encircling the horizontal strands and abutting upright strands of the ofiset portions of the said springs, said connecting spring being of such diameter as to force the axial offset portions into engagement with one another.

2. In'a spring structure, the combination with a pair of adjacent supporting springs having complementary contiguous portions axially offset inwardly to provide upright strands and horizontal strands, of a connecting spring including a helical coil encir-' cling the horizontal strands and abutting upright strands of the offset portions of the said springs, said upright strands being staggered in accordance w1th the pitch of the coil of said connectingspring, and said connecting spring being of such diameter as to force the axial offset portions into engagement with one another.

3. In a spring fabric, the combination of a series of rows of coil springs having their end coils substantially in a common plane and provided with hinge portions offset inwardly from such plane, and connecting means securing the respective hinge portions of each spring to the hinge portions of other springs beneath the said plane, said connectiliig means comprising helical springs and the 0 set connecting portions of the several supporting springs comprising substantially upright strands engaged by the successive coils of the helical springs to be positioned thereby, said helical spring being of such diameter as to force the axial ofiset portions into engagement with one another.

4. A spring structure comprising adjacent rows of helical supporting springs, corre REINHOLD W. MARQUARDT. 

